VCRs (video cassette recorders) have found nearly universal acceptance as a way to record and distribute audio/visual entertainment content such as motion pictures. These devices use a magnetic tape medium to store audio and video content. VCRs allow recording of several hours of audio/video content, which can then be played back as desired.
One disadvantage of VCRs and their associated tapes is the difficulty of indexing to an intermediate point in the taped content. Because of the linear nature of magnetic tape, it must be manually advanced to the point containing the desired content. Advancing the tape in this manner can take several minutes.
Another limitation of the linear tape format is that only one portion of the tape can be played or recorded at any given instant—it is not possible to record on one portion of the tape while playing back another portion.
These limitations have been addressed in newly emerging devices by storing digitized audio/video content on conventional hard disks. This has been made possible by the continually decreasing cost of hard disk storage. With a hard disk, it is possible to simultaneously record received audio/video on one portion of the disk, while also playing back audio/video from another portion of the disk.
Hard disk recording of broadcast television signals has enabled several features. One of the simplest features enabled by this technology is the ability to “pause” a broadcast television show and then “resume” it without missing any of the content. When the viewer initiates a pause, the viewing device begins recording the show to disk. When the viewing device receives a subsequent resume command, the recorded content is played back to the viewer, while the device continues to record remaining portions of the show. Thus, although the broadcast transmission has continued normally, the user perceives the ability to control the transmission just as if he or she had been watching the show from a recorded VCR tape.
Another feature is the ability for a viewing device or so-called “set-top box” to learn viewing habits and to automatically record favorite shows. The user can then select shows for viewing from an electronic program guide, and watch those shows from hard disk even if the shows have already concluded. This method of interacting with a recording device is much more convenient than present methods of programming VCRs.
These features and others enabled by disk recording technology promise to revolutionize the way broadcast content is distributed and consumed. However, these features also threaten to overwhelm viewers with viewing choices. The technology described below provides ways for a viewer to “skim” through recorded content, providing a new way to deal with the overwhelming volume of broadcast content that is becoming available.